Field of the Invention
The invention is generally related to airblasting various objects and is specifically directed to a containment system for airblasting pipes and similar objects while containing the blasted portion in a confined and closed chamber.
Discussion of the Prior Art
It is known in the art to apply or propel various substances, materials and/or media, both abrasive and non-abrasive, against a desired surface in order to treat the surface, e.g., polish, clean, abrade, prepare a surface for painting, remove rust, grease or oil and the like. The blasting media may consist of dry or liquid material or a combination thereof with or without a variety of abrasive or non-abrasive constituents added thereto. In many applications, the blasting media is a composite media comprising a combination of two or more components which are mixed or blended together with one another, in the desired proportion, to achieve the desired surface treatment. Application of the blasting media by means of a pressurized applicator generally results in a substantial quantity of media and contaminants becoming airborne and rebounding off of the surface being treated.
The state of the art for blasting external surfaces of pipes, rods and similar objects is to “open blast”. This is airblast in an open environment. This process creates many issues. First, the grit and dust are allowed into the open where they will be carried with the wind or fall onto the ground. If the paint or surface contains hazardous material, this may result in air or ground pollution or contamination. Also, the operator must wear protective equipment such as respirator for the dust and protective clothing to withstand the impact from rebounded grit or abrasives.
It is desirable that this rebounding media be adequately contained within an enclosed treatment area in order to prevent contamination to the surrounding environment with the media and/or removed contaminants and/or debris from the surface being treated. This is especially true if hazardous materials are being removed from the surface being treated. In order to protect the operator it is known to have contained nozzles that are automated and mechanized to blast exterior surfaces of pipe. It is also known to use handheld blast and vacuum heads to blast and treat the exterior surface of the object being treated. Such mechanized systems are generally heavier, very expensive, and slower to setup. The handheld blast and vacuum heads also generally have slow production and the nozzle is at a relatively fixed orientation. Also, handheld heads require exertion from the operator to maintain a seal while blasting. This makes them subject to operator error and subject to familiarity and experience. Neither of the aforementioned systems allows vision so the blaster (operator) is blind to the activity or progress. Vision is desired, if not required, in situations where the operator requires precise control of the area to be blasted.
There are also containment systems currently known in the art are which are used in the treatment of such objects. These systems contain the blasting media and other material, contaminant, debris and hazardous material in order to suppress the harmful effects to a confined area. However, to treat these objects or surfaces, generally an operator would be required to be inside the containment area and thus subjected to such hazardous conditions and do not eliminate the need for the operator to wear protective clothing and use protected, filtered breathing apparatus. These type of containment systems are relatively large and require much labor to set up.
U.S. Pat. No. 8,556,683 discloses a containment barrier for containing a blasting media during treatment of such objects, the containment barrier being defined by a peripheral housing having three or more body surfaces and two end surfaces, defining an enclosed treatment area. A viewing aperture is located within a first body surface, with a transparent member being placed within the viewing aperture to contain blasting media within the enclosed treatment area while enabling observation of the object being treated. An elongate access aperture is located within one of the body surfaces, and an elongate cylindrical access port body is rotatably fixed within the access aperture to allow restricted access to the enclosed treatment area for enabling insertion of one or more tools used during the treatment the object. The access port body has an elongate tool inlet and an opposed elongate tool outlet. The interior of the access port body includes a tool retainer slidable along the elongate port body for allowing directed treatment of the object along a first axis. The port body is rotatably fixed at opposed ends for enabling axial rotation of the port body allowing directed treatment of the object in a second axis. The tool inlet is substantially enclosed by a seal. A media evacuation system including one or more exhaust hoses is used to evacuate the spent media.